why does have to short-circuit secondary wire of current transformer ?
transformer is busted; if input voltage is normal you have short circuit or open circuit somewhere
When the secondary of a transformer experiences a sudden short circuit, it causes a drastic increase in current flow through the secondary winding. This results in a significant drop in secondary voltage due to the short circuit conditions. As a consequence, the primary winding will also experience a corresponding increase in current, which can lead to overheating and potential damage to the transformer if protective measures are not in place. The transformer's ability to handle this situation depends on its design and the effectiveness of protective devices such as fuses or circuit breakers.
There is no disadvantage with a current transformer -it does exactly what it's supposed to do, that is:reduce the current flowing in the primary circuit to a value that can be handled by its burden (ammeter or protective relay).electrically-isolate its secondary circuit from the primary circuit.
A current transformer doesn't 'measure current'. It merely reduces a large current flowing through its primary to a smaller current which can be read by an ammeter connected to its secondary. At the same time, it electrically isolates the secondary circuit from the primary circuit, which is essential if the primary circuit is part of a high-voltage system.
why does have to short-circuit secondary wire of current transformer ?
A magnetic transformer works by transferring electrical energy from one circuit to another through electromagnetic induction. When an alternating current flows through the primary coil of the transformer, it creates a changing magnetic field. This changing magnetic field induces a voltage in the secondary coil, which then transfers the electrical energy to the secondary circuit. This process allows for the conversion of electrical energy from one circuit to another with minimal loss.
The function of an isolation transformer is to electrically-isolate the secondary circuit from the primary circuit, without changing the voltage levels. So, its secondary voltage will be the same as the primary voltage.
transformer is busted; if input voltage is normal you have short circuit or open circuit somewhere
A secondary current of 0 would suggest to me that the secondary circuit is open. A normally operating circuit with zero current flow would be very unusual. No load in secondary circuit. No secondary current can also be attributed to the primary power source open or an open primary winding.
When the secondary of a transformer experiences a sudden short circuit, it causes a drastic increase in current flow through the secondary winding. This results in a significant drop in secondary voltage due to the short circuit conditions. As a consequence, the primary winding will also experience a corresponding increase in current, which can lead to overheating and potential damage to the transformer if protective measures are not in place. The transformer's ability to handle this situation depends on its design and the effectiveness of protective devices such as fuses or circuit breakers.
A short-circuit test is done to determine the power lost in the resistance of the primary and secondary windings of the transformer. It is done at full load current but with only enough voltage to give the required current with the secondary short circuited. An open-circuit test is done at full load voltage but no current is taken from the secondary, and this enables the power lost in the magnetic core of the transformer to be measured. As well a power, the tests also allow the inductances to be measured as well as the resistances, in order ot characterise the transformer fully.
The difference between a double wound step up transformer and an auto transformer is the double wound on the step up transformer and the single wound on the auto transformer.
There is no disadvantage with a current transformer -it does exactly what it's supposed to do, that is:reduce the current flowing in the primary circuit to a value that can be handled by its burden (ammeter or protective relay).electrically-isolate its secondary circuit from the primary circuit.
depends on the type of trans former.buck or boost.primary winding a secondary winding
A current transformer doesn't 'measure current'. It merely reduces a large current flowing through its primary to a smaller current which can be read by an ammeter connected to its secondary. At the same time, it electrically isolates the secondary circuit from the primary circuit, which is essential if the primary circuit is part of a high-voltage system.
A voltage transformer takes a primary voltage and steps it down to a smaller secondary voltage. This type of transformer will attempt to keep the secondary voltage at a specific ratio of the primary voltage. If you short it, massive current flow in the secondary is required to do this. For a similar reason a CT should never be open circuited - because it attempts to push a specific ratio of primary current through the secondary. If you open circuit the secondary, it takes a massive voltage on the secondary to accomplish this.